TY - JOUR
T1 - Signature of multiradical character in second hyperpolarizabilities of rectangular graphene nanoflakes
AU - Nagai, Hiroshi
AU - Nakano, Masayoshi
AU - Yoneda, Kyohei
AU - Kishi, Ryohei
AU - Takahashi, Hideaki
AU - Shimizu, Akihiro
AU - Kubo, Takashi
AU - Kamada, Kenji
AU - Ohta, Koji
AU - Botek, Edith
AU - Champagne, Benoît
N1 - Funding Information:
This work was supported by Grant-in-Aid for Scientific Research (Nos. 21350011 and 20655003 ) and ‘ Japan-Belgium Cooperative Program ’ ( J091102006 ) from Japan Society for the Promotion of Science (JSPS), Grant-in-Aid for Scientific Research on Priority Areas (Nos. 18066010 , 20038012 and 20350002 ) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT), and the global COE (center of excellence) program ‘Global Education and Research Center for Bio-Environmental Chemistry’ of Osaka University. Theoretical calculations were (partly) performed using Research Center for Computational Science, Okazaki, Japan. E.B. thanks the Interuniversity Attraction Pole on ‘Functional Supramolecular Systems’ (IUAP No. P6-27) for her postdoctoral grant. This work has also been supported by the Academy Louvain (ARC ‘Extended π-Conjugated Molecular Tinkertoys for Optoelectronics, and Spintronics’).
PY - 2010/4/9
Y1 - 2010/4/9
N2 - Using spin-unrestricted density functional theory methods, the second hyperpolarizabilities, γ, of rectangular graphene nanoflakes of different sizes have been investigated for their singlet ground state in conjunction with their open-shell character. It is shown that their multiradical nature leads to a unique dependence of the γ component along the armchair edges and that this behavior can be rationalized not only in terms of the diradical character (y0) derived from the HOMO and LUMO occupation numbers, but also in terms of the one (y1) derived from the HOMO-1 and LUMO+1 ones: the γ components are enhanced when the systems take intermediate y1 values in addition to intermediate y0 values.
AB - Using spin-unrestricted density functional theory methods, the second hyperpolarizabilities, γ, of rectangular graphene nanoflakes of different sizes have been investigated for their singlet ground state in conjunction with their open-shell character. It is shown that their multiradical nature leads to a unique dependence of the γ component along the armchair edges and that this behavior can be rationalized not only in terms of the diradical character (y0) derived from the HOMO and LUMO occupation numbers, but also in terms of the one (y1) derived from the HOMO-1 and LUMO+1 ones: the γ components are enhanced when the systems take intermediate y1 values in addition to intermediate y0 values.
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U2 - 10.1016/j.cplett.2010.03.013
DO - 10.1016/j.cplett.2010.03.013
M3 - Article
AN - SCOPUS:77950002150
SN - 0009-2614
VL - 489
SP - 212
EP - 218
JO - Chemical Physics Letters
JF - Chemical Physics Letters
IS - 4-6
ER -